Device for measuring torsion



. Parental July 9,1929. l i 1,720,582

UNITED STATES PATENTOFFICE.

VOLIHLB VIEWEG, F CHARLOTTENBUBG, NEAR BERLIN, GERMANY.

DEVICE FOR MEASURING TORSION.

Application led December 29, 1926, Serial No. 157,827, and in Germany October 29, 1924.

For the measurement of forces various deshaft; a and serving for indicating the torvices are known which are based on the obsion and thus the force acting, is totally en- 45 servation ofthe torsion of a resilient part. closed as by a casing by parts e which are se- These instruments have, however,` in general cured to the disc l which also serves for inthe disadvantage that the members serving dicating purposes and are thereby connected for indicating the force in rotating `produce with the other'measuring cross section 2-2. losses due to the eddying of the air and such The relative motion between the parts 50 disturbances have an adverse effect. in certain and al can be observed in the same manner as measurements. A has been explained in applicants copending The invention has for its object the avoid. application Ser. No. 62864 of which the presance of this disadvantage. ent application is a division.

Thus there exists torsion indicators in For observing the means relative torsion 55 which the twist of the resilient part between of the two cross sections 1 and 2 the disc two measuring cross sections is determined. (I is provided with an opening m in the inid- IVith the measuring cross section there are asdle o'tl which an index thread t is fastened.

sociated parts serving for indication of the Opposite to said opening m on the adjacent torsion and thus of the forces acti-ne. side of the disc a scale n is provided l'or. 60

Under the'fpresent invention the parts of Alsocorresponding totheopening m,an'1irror the instrument'. connected with the one measo with aninclination of 45 degrees is secured uring cross section and rotating therewith to the projecting part d of the, disc (l by are enclosed by parts which are connected meansof a. 'fasteningdevice f] and tlnrdistance with thc other measuringr cross section and ro- 1' from the middle ofthe mirror o to the space 65 tating therewith as by acasing. Within this between thedisc and d being equal to the casing air friction is not produced and they distance s lfrom thc middle ot' the mirror o to enclosed parts have no motion relative to the the middle of the shaft a.

walls. On the side ofthe measuring cross lf the shaft n. is rotating with both meassection connected with the enclosed parts urng cross-sections l and 2, an eye. u being 70 which according to the purpose of the measin the direction p can observe in the moving urement is located adjacent the driven orthe mirror o the degree of the mean relative tordriving side of the vrotating system, the inlsion ot' the cross-scctiims l and 2 owing to the Cil strumentis free from losses dile to air friction. displacing of the index-thread relative to the The arrangement of a torsion indicator as a scale n. 75 casing is not unusual but in such indicators as 'hat I claim is: have been proposed astationary lamp or fixed f Device for avoiding the air eddy losses of source of light is provided which produces'air torsion measuring instru-ments for a transfriction which it is the object of the present mission shaft, said device including parts coninvention to avoid. In apparatus employing nected to the oneI cross-section ot' the shaft S0 a stationary housing naturally air friction and parts connected with another cross-sccwill be produced. tion of the shaft, said last-mentioned parts 4o The application ofI the invention to a tortotally enclosing said first-mentioned parts.

sion indicator is illustrated in the accompany- In testimony whereof I have signed my ing diagram. As shown the disc b, connected 4name to this specification. with the measuring cross section 1-1 of the VOLKMAR` VIEWEG. 

